Magnesium alloys are lightweight materials—they are 30 to 50 percent lighter than aluminum alloys and 70 percent lighter than steels. Additionally, magnesium alloys have good strength characteristics and stiffness, excellent damping and mechanical properties, and they resist corrosion. Therefore, magnesium alloys are used as structural materials in the aerospace, automobile and rail transportation industries, and are used in various products, such as household appliances.
Magnesium alloys are typically divided into two categories: cast magnesium alloys and wrought magnesium alloys. Cast magnesium alloys can have coarse grains and can exhibit compositional segregation. Therefore, cast magnesium alloys often fail to satisfy the stringent physical requirements of today's high-performance structural materials. Wrought magnesium alloys typically exhibit better mechanical properties, such as proof stress, tensile strength and elongation, as compared with cast magnesium alloys. Therefore, wrought magnesium alloys are often considered for use as high-performance structural materials, particularly when weight is an important consideration.
The common wrought magnesium alloys include the magnesium-aluminum-zinc series and the magnesium-zinc-zirconium series. AZ31 is a typical alloy of the magnesium-aluminum-zinc series—AZ31 has moderate strength, but poor high temperature strength performance. ZK60 is a typical alloy of the magnesium-zinc-zirconium series—ZK60 has excellent room temperature and high temperature strength performance, but is relatively expensive.
Accordingly, those skilled in the art continue with research and development efforts in the field of magnesium alloys.